Strands are typically rendered antimicrobial by doping with heavy metal ions, such as silver ions, or by applying antimicrobially active sizes to the strand surface. Attempts have also already been made to incorporate antimicrobially active substances in the strand, but this is generally limited to selected materials and the active substances are comparatively rapidly removed from the strand by washing.
Halogenated phenols are known as useful antimicrobial agents. One example is triclosan, 2-hydroxy-4,2′,4′-trichlorodiphenyl ether.
Examples of antimicrobial strands are to be found in CA-A-2,551,701, which describes a microbiocidally active air filter comprising microbiocidal strands. Triclosan is one example of an antibacterial agent mentioned; polyvinyl chloride is proposed as strand-forming material.
DE-T-699 08 910 describes antimicrobial strands or textiles. The antimicrobial property is imparted by surficial application of triclosan or a derivative thereof to the strand or textile surface. It is stated in the description that the co-extrusion of triclosan with strand-forming materials is only possible with selected polymers and does not work with polyester textiles, polyamide textiles, cotton textiles and lycra textiles.
U.S. Pat. No. 6,299,651 discloses textiles finished with etherified triclosan derivatives. The active substance is applied by contacting with the surface of the strand or textile at a temperature sufficient to effectuate diffusion into the strand or textile.
DE-T-689 09 268 describes a method of altering the surface of a solid synthetic polymer wherein a surface is contacted with a basic swelling agent. The altered surface can be used to introduce active substances into the synthetic polymer.
We have now surprisingly found a selected group of spinnable polymers which permit the introduction of large amounts of halogenated phenols and which permit the production of elastic strands having a hitherto unavailable performance profile. It has emerged that spinning thermoplastic elastomers with halophenols in the form of a masterbatch gives such strands.